ON VEGETABLE PHYSIOLOGY. 87 



and others, (and those more generally) to the 

 exciting action of the sap itself upon the irritable 

 fibres of the vessels, causing them to contract 

 and propel the fluid upwards. 



I shall conclude this day's paper by a few 

 observations upon the varieties and uses of the 

 vegetable kingdom. 



In our daily observation, the surrounding vege- 

 table substances are so constantly before our 

 eyes, and many of them in such habitual use, 

 that we are too apt to pass them by as unworthy 

 of our regard ; and unless some striking feature 

 of country, or some peculiarity in its productions 

 awaken our attention, to neglect an investigation 

 which, by a more laudable curiosity, would have 

 afforded us a gratification of the deepest interest. 



In this, and in many other countries of Europe, 

 with a climate unfavourable to luxurious growth, 

 and where cultivation has subjected the principal 

 portions of the soil to the domestic uses of man ; 

 vegetation may be considered to be nearly artifi- 

 cial, and nature is only seen under a disguised 

 garb; evincing indeed to what perfection, through 

 skill and industry, the minor or herbaceous species 

 of the vegetables may be brought, but excluding in 

 a great measure from our observation, those gran- 

 der productions of the vegetable world, which at 

 once astonish us by the magnitude of their growth 

 and the variety of their species, by the noble ex- 

 pansion of their foliage, and by the unrivalled and 

 variegated tints of their blossoms and fruits. 



